While almost every mainstream anthropologist continue to babble out-of-Africa, German Dziebel alone takes the brave step to the very opposite, i.e. out-of-America(s). Therefore, dear reader, it's quite logical that "extremely normal" and cautious Klevius cowardly settles in the middle.
However, here's German Dziebel's view on human evolution
Fully Integrated and Multidisciplinary Model of Modern Human Origins: Out-of-America, with ultimate origins from an East Eurasian hominid, and into Africa with admixture with extinct African archaic hominins.
This model that I consider to best reflect core interdisciplinary evidence for modern human origins (ethnology, linguistics, population genetics, paleobiology, archaeology) postulates that behaviorally and anatomically modern humans originated from a population of East Eurasian humans such as Neanderthals (whose geographic reach stretched all the way to the Altai Mountains in southern Siberia and, possibly, beyond the Arctic Circle in the northwestern Urals), Homo erectus or Denisovans (the newly-discovered hominid species attested through a tooth and a pinkie from the Denisova Cave, South Siberia).
Between 200,000 and 100,000 years ago, a subset of this original hominid population migrated to the New World (via the Bering Strait Land Bridge), where speciation into modern humans occurred. While, under out-of-America II, the unique social behaviors shared between modern humans and New World primates (pair bonding, paternal investment, cooperative breeding and speech) are interpreted as homoplasies, the fact that such key aspects of human social and cognitive behavior are shared with Platyrrhines suggests that the immediate ancestors of modern humans were exposed to the same New World environment as the New World monkeys.
This migration into a new continent via a relatively narrow land bridge resulted in a population bottleneck still visible in the human genome (as compared to other primate genomes) and in the Amerindian genome.
With the next retreat of the ice shield, our ancestors migrated back to the Old World and replaced, possibly with some admixture, all Old World hominids in Eurasia and Africa. As a result of this re-expansion in the Old World, all human populations, with the exception of American Indians (and arguably such isolates as Papua New Guineans, the peoples of the Caucasus and the Hadza of Tanzania), somewhat rebounded from the original bottleneck due to population size growth, waves of intraspecific admixture and, possibly, admixture with archaic hominids in Eurasia and Africa.
This replacement of Old World hominids by the modern humans coming out of America corresponds to the emergence of signs of modern human behavior all over the globe around 40,000 years ago.
One clear advantage of Out-of-America II over Out-of-Africa is that prolonged geographic isolation is an absolute prerequisite for a speciation event to occur. Africa had been well settled by ancient hominids to allow for the easy and matter-of-fact speciation into modern humans in Africa that’s assumed by the mainstream science of human origins. The emergence of a new hominid species with a radically different, worldwide adaptation based on an advanced system of symbolic thinking and social cooperation followed by the dramatic replacement of pre-existing hominids all over the world is best explained as having its origin in a unique original environment – on a continent previously unexplored by hominids.
Another advantage of Out-of-America II over Out-of-Africa is that it’s consistent with ancient DNA results: while we don’t have a single ancient DNA sample to ascertain whether modern African populations are directly related to ancient “anatomically modern humans” (e.g., Omo, Herto, etc.) and hominids in Africa, we do have ancient DNA data (X chromosome, autosomes, blood groups) that document matches between Neanderthal and Denisovan genetic variation, on the one hand, and modern humans in the New World (and in Melanesia). While these matches are currently interpreted as a sign of admixture between Africa-derived modern humans and in-situ hominids, they are the only signs of continuity between archaic and modern humans known to science at this moment.
After speciation in the New World had occurred, early Homo sapiens sapiens colonized first Eurasia and then Africa replacing and admixing with local hominids. Admixture with archaic hominins in Africa was more substantial than in Eurasia, which is reflected in the firmly established excess in intragroup genetic diversity in Africa.
This model uses Y-DNA evidence, namely the phylogenetic position of the major African E clade as a subset of the non-African DECF clade, as evidence for the extra-African origin of modern humans.
Back in 1998, the Michael Hammer lab published a paper entitled “Out of Africa and Back Again: Nested Cladistic Analysis of Human Y Chromosome Variation,” in which a major back-migration into Africa accounting for the majority of African Y chromosomes was proposed. Haplogroups A and B found exclusively in Africa are explained as either the product of admixture between African hominids and the incoming modern humans or as retentions from the earliest, purely African phase in the modern human evolution. Archaeologically, the presence of sites such as Dabban, with clear Upper Paleolithic roots, in North Africa around 40,000 YBP supports the back-migration idea.
From the paleobiological perspective, the Hofmeyr skull in South Africa dated at 36,000 YBP clusters with Upper Paleolithic Eurasians, which, again, suggests that Africa was peopled from Eurasia, not the other way around.
Another argument in favor of an extra-African origin of modern humans is the fact that skulls with archaic features survived in various part of Africa (e.g., the Iwo Eleru skull dated at 11-16,000 YBP or the Lukenya Hill calvaria in Kenya at 23-22,000 YBP). If there was indeed continuity between “anatomically modern humans” in Africa that begin to show up in the paleontological record from 200,000 BP on and today’s anatomically and behaviorally modern humans, we would not expect archaic hominins to survive in Africa for almost 180,000 years.
Outside of Africa, modern humans needed only a short window to replace all of the Neanderthals. It’s also noteworthy that African megafauna was largely spared in Africa: only 14% (or 7 out of 49 genera) of African megafauna went extinct in the Late Pleistocene. Outside of Africa, megafauna extinctions were much more dramatic, with 86% of megafauna going extinct in Australia, 80% in South America, 73% in North America, 60% in Europe.
Under the anthropogenic theory of megafauna extinctions, modern human hunting and ecological disruption are the causes of the extinctions. If Africa was the least affected continent, it’s possible that it was peopled by modern humans later than other continents and/or by smaller numbers of modern humans. But genetics predicts otherwise – Africa must be the oldest and most populous continent, hence modern Africans are more diverse than populations outside of Africa.
If anatomically and behaviorally modern humans originated at a place in Sub-Saharan Africa and expanded first across all of Africa (as the distribution of “basal” mtDNA and Y-DNA lineages in current phylogenies seems to suggest), then it’s unclear why the megafauna was not affected by their new and improved hunting practices. But the anthropogenic theory of megafauna extinctions is just one theory out of many and climate change may have been a bigger factor.
and here's
German Dziebel's evaluation of some other bloggers on the topic:
There are several weblogs out there that consistently cover topics related to human origins, human dispersals and human prehistory. They fall into different genres, profess different policies and have different, albeit overlapping audiences. Over the past few years, I have engaged with all of them as an observer, guest blogger and/or commenter. My unorthodox views spurred bitter controversy on a number of occasions and exposed the lack of culture of scientific objectivity and civil open-mindedness on most weblogs. Below are my quick reviews of these weblogs borne out of two years of ethnographic participant observation on them. Despite my critique, all of the following weblogs are worth following.
John Hawks Weblog: Paleoanthropology, Genetics and Evolution. An academic weblog by an associate professor at University of Wisconsin – Madison. A good solid read on population genetics and paleobiology. Some fresh news related to complete genome sequencing from his own lab. Webcasts of Hawks’s lectures are also very informative. Little to nothing on language, culture or critical thinking. Lacks a big picture vision. Perhaps Hawks is more of a human or even primate biologist that has some experience with human diversity, mainly through working with blood samples, body parts (e.g., ears) and bones. He considers himself “paleoanthropologist,” but it’s a questionable label. The only evolutionary angle on anthropology that makes sense is the study of the origin of modern human biological, social, cultural, linguistic complexity. But Hawks apparently carves out the study of human remains (hence “paleo-“) as a branch of anthropology, which it is not. Hawks started as a maverick: a student of Milford Wolpoff’s, he maintained loyalty to Multiregionalism through the “Complete Replacement Out of Africa” era and since the discovery of “archaic admixture” in modern humans feels himself vindicated. Consistent with this identity transformation, Hawks’s weblog used to sport his image made in Neandertal liking (Hawks always believed that Neandertals did not go extinct, hence Hawks as a Neandertal was more than a metaphor) but now features John in an Indiana Jones hat. His self-imposed celebrity status is reinforced through a gallery of John Hawkses in various intellectually credible environments. The blog is also a travelogue of Hawks’ trips to some holy archaeological sites such as the Denisova Cave and a twitterlog of his engagement with social media. While antiquated and one-sided in his interpretation of anthropology, John Hawks is an early adopter of Internet technologies, open-source mentality and 140-word style of communication with the world. You can’t leave a comment on his weblog, but you can write him an e-mail. I sent him one, he never replied.
Dienekes Pontikos’s Anthropology Blog. This blog is the best place to gather news and links to mainstream academic human origins research. An anonymous Greek author based in Kavala, Greece, the home to the Pontian Club, has evolved from a curious reader of academic articles to an independent and opinionated genome blogger dabbling in software analysis of autosomal genetic sequences. His other blog, Dodecad, is dedicated to more in-depth ADMIXTURE, ChromoPainter and other runs, with a focus on narrower regional comparisons. Dienekes’s thinking is in a state of flux: modern humans originated in Arabia or India and migrated back to Africa and also that there was a population structure in Africa and strong admixture with archaic hominids in Africa. These ideas make the blog an interesting read, as it does not simply recycle academic consensus. He has some secret agendas related to gender and racial inequalities (this subsided somewhat in the past couple of years, as Dienekes became busy with applying computer software to human samples) and believes in the “purity” of quantitative science. He is an armchair science hobbyist (“anthropology” in the title of his weblog is a product of his imagination) and a naive statistician who maintains an idealized notion of what science is, and has no theoretical understanding of how make inferences about prehistory, thus creating confusion around the notions of common descent, admixture and convergent evolution. Berating linguistics as a poor predictor of ancient population history is commonplace on Dienekes’s Anthropology Blog; for some reason, Dienekes assumes that good science leaves no room for ambiguities and enigmas. He censors critical comments that he does not know how to respond to and likes to unleash scathing critique of opinions of his least savvy readers.
Gene Expression. An anti-liberal, anti-creationist and anti-socialscience blogger, Razib Khan, blogs about everything from European history to Google Trends. Religion, politics, medical and population genetics, race are Razib’s favorite topics. His “pinboard feed” is a good news source. He is a quick and well-read thinker who provides an interesting mix of journalism and data analysis but lacks focus on what the blog is all about and why is it that he blogs. It’s unclear why Discover chose to host Gene Expression. Verbose, superficial and self-infatuated on the main pages, Razib tends to be condescending and rude in the comments section. He retaliates aggressively against those who poke at his ego as an expert on skin color or as a noble defender of science against infidels such as Native American tribes who wouldn’t surrender their blood samples. But apparently Razib’s boss at Discover loves him. Razib’s audience is mostly composed of curious bystanders to science whom he educates about Darwinism, race and population genetics and for whom he summarizes books and pay-per-view articles. Razib thinks the world of science buffs owes his because he briefs them on science for free, and therefore he’s entitled to bludgeon them verbally at will. Openly political in his judgments, he sports “degrees in biochemistry and biology” (he used to bill himself as having a “background” in these fields but apparently at some point he started feeling threatened by something and decided to beef up his credentials), admits ignorance of linguistics and is allergic to the majority of anthropologists. He enjoys mentorship and support from such marginal academic anthropologists as Henry Harpending and John Hawks as well as from a cantankerous maverick Greg Cochran. The latter usually uses Razib’s comments section to make a caustic remark about something or someone he hates. There are a few serious biologists and geneticists who every now and then leave intelligent and spirited comments on Razib’s blog, but it’s impossible to say who those people are.
For What They Were…We Are: Prehistory, Anthropology and Genetics. This weblog stands out as an epitome of Internet’s democratic and grassroots mission. It’s authored by a Basque anarchist, Luis Aldamiz, who goes by coy alias Maju. He vents his frustrations against the modern world at his other weblog and uses human origins research as a way to find a peaceful home for his troubled personality. He dabbles in everything from linguistics to the origin of life. Apart from the unfortunate color scheme, a meandering title and an odd claim to “anthropology” in the subtitle, this weblog is 95% repetitive of Dienekes’s Anthropology Blog and Gene Expression when it comes to population genetics. At the same time, he spends more time than other weblogs on archaeological news and news related to the prehistory of the Basques. His approach to science writing falls into two categories: it’s either a loud protest against “bad” theories (an example would be a well-supported theory of replacement of foragers by agriculturalists in Europe) or a loud advocacy for “good” theories (such as the Complete Replacement Out-of-Africa, which, to his surprise, got recently falsified), with no real theories of his own to be intrigued by or shades of color in the presentations of the theories of others to enjoy. On the other hand, his comments section is a must-read, as it’s a perfect dungeon of cage fighting where Maju wields his eye-gouging and hair-pulling verbal tactics in grueling, no-holds-barred 12-rounders on the topic of mtDNA sublineages against an angelic reader from New Zealand, Terry Toohill. After having tested Terry’s stamina for verbal abuse for a couple of years, Maju’s anarchist self revolted against Terry’s steadfast mind-controlling purposefulness. As a result, Terry got banned from the blog, to the chagrin of many spectators like myself. Maju also travels all around the Web engaging on various forums: often with the teeth-clenching power of a cartoonish Neanderthal he rips other people’s arguments into pieces to gnaw on each bit in search of flawed logic or bad data support; however, to some academic bloggers such as archaeologist Julien Riel-Salvatore at Very Remote Period Indeed, he suddenly shows the other side of his personality, the one that is courteous, partial and self-effacing. A work-in-progress is Maju’s Human Prehistory and Genetics Wiki, a “private” wiki composed by Maju and a couple of his regular commenters (such as Terry Toohill). It currently looks like pullouts from Wikipedia on the distribution of mtDNA and Y-DNA lineages. For a while, Luis Aldamiz was trolling various science forums and his own website assuming the posture of a “science defender,” obsessively informing readers about the pernicious aspects of my out-of-America hypothesis and defaming my name (e.g., here, here, here, here and here). I took it to his own comments section and he stopped his anti-Dziebel campaign. A couple of years later he suddenly posted on his website a list of trolls, with my name among them. But I don’t comment on his site and have never had any interest in doing it, so it was a sheer lie. Most recently, Aldamiz stopped blogging altogether because he got overwhelmed by unknown trolls. One can only cheer when a troll gets consumed by other trolls.
Sounding Depths, Music 000001. These 1+1=2 weblogs by ethnomusicologist Victor Grauer are the two most underrated web-based contributions to modern human origins research. One of the reasons why they are underrated is because they are online books, rather than weblogs. They are updated irregularly and represent Grauer’s thoughts and knowledge accumulated over decades, rather than his on-the-fly reactions to incoming research studies or news items. The other reason is that Grauer’s expertise in an arcane field of music, which nobody engaged in the search for the origins of modern humans understands. The comments traffic on Grauer’s weblogs has been low, and there’s no engagement with his ethnomusicology on any other weblogs or in academic publications dealing with human origins. The third reason is Grauer’s antiquated and naive vision of anthropology and historical reconstructions (his M.A. in Ethnomusicology is from 1961): he freely engages in tropical fantasies (for him, just like for early diffusionists, Pygmies are pristine remnants of earliest humans); his command of population genetics is superficial and confused (which Grauer willingly admits) but he uses it as as a “north star” guiding his analysis of global musical traditions; he’s strangely condescending to linguistics and other non-biological disciplines and implies that music somehow maps onto neutral genes directly, bypassing other biological, social and symbolic systems; as a naive evolutionist he uses everything from modern dwellings to modern human height to modern body paint as representing either passive retentions from primordial Mid-Pleistocene African adaptations or forced innovations caused by the founding migration out of Africa and the Toba eruption. He readily sees continuities between Pygmy and Bushmen vocalizing, on the one hand, and the sounds of bonobos and baboons, on the other, but when it comes to comparing Bushmen and Pygmy singing with the vocal traditions of non-African peoples, all he sees are discontinuities caused by population bottlenecks and, again, Toba eruptions. His ideas rise to an almost Biblical pitch when he portrays ancient Africans as non-violent multi-part singers living in the tropical forest and carrying undiversified human mtDNA lineages – an Edenic idyll superseded by violence and the breakdown of traditions among the out-of-Africa migrants. These weaknesses and oddities aside, there’s nobody out there beside Grauer who has the command of global musical traditions, has a systematic method of comparing them (he inherited cantometrics from his mentor Alan Lomax) and can show how they can be plausibly interpreted as reflections of ancient population movements. In this sense, Grauer’s contribution is invaluable and, unlike many other weblogs, Sounding Depths and Music 000001 actually add value to human origins research. But sometimes I wish they sounded more like a contemporary scientific study than a Wagnerian opera.
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